tireless; showing sustained enthusiastic action with unflagging vitality
The indefatigable researcher worked for decades on her groundbreaking study.
Vocabulary like indefatigable appears on the Digital SAT in Words-in-Context questions, where you choose the word that fits a passage's meaning and tone. You can also drill this word with vocabulary flashcards.
disconnected; without logical or meaningful connection
incompatibility; the quality of disagreeing; being unsuitable and inappropriate
absurd; lacking in harmony or compatibility or appropriateness
not important
difference; the relation between propositions that cannot both be true at the same time
bodiless; without material form or substance
impossible to correct; impervious to correction by punishment
current holder of an office; the official who holds an office